Plastic pollution at the nanoscale continues to pose adverse effects on environmental sustainability and human health. However, the detection of nanoplastics (NPLs) remains challenging due to limitations in methodology and instrumentation. Herein, a “green approach” to surface-enhanced Raman spectroscopy (SERS) was exploited to detect polystyrene nanospheres (PSNSs) in water, employing an untreated filter paper and a simple syringe-filtration set-up. This SERS protocol not only enabled the filtration of nano-sized PSNSs which are smaller than the pore size of the ordinary filter paper but also offered SERS enhancement by utilizing quasi-spherical-shaped silver nanoparticles (AgNPs) as the SERS-active substrate. The filtering of NPLs was accomplished by adding an aggregating agent to the nanoparticles mixture, which caused the aggregation of NPLs and AgNPs, resulting in a larger cluster and more hot spots for SERS detection. The optimal aggregating agent and its concentration, as well as the volume ratio between AgNPs and NPLs, were also optimized. This SERS method successfully detected and quantified PSNSs of various sizes (i.e., 100, 300, 460, 600, and 800 nm) down to a limit of detection (LOD) of about 0.31 μg/mL. The method was also validated against the presence of several interferents (i.e., salts, sugars, amino acids, and surfactants) and was proven practical, as evidenced by the detection of 800-nm PSNSs in drinking and tap water (LODs of 1.47 and 1.55 μg/mL, respectively).
{"title":"A Green Approach to Nanoplastics Detection: SERS with Untreated Filter Paper for Polystyrene Nanoplastics","authors":"Yukihiro Ozaki, Prompong Pienpinijtham, Yunfei Xie, Sanong Ekgasit, Mary Jane, Boonphop Chaisrikhwun","doi":"10.1039/d4an00702f","DOIUrl":"https://doi.org/10.1039/d4an00702f","url":null,"abstract":"Plastic pollution at the nanoscale continues to pose adverse effects on environmental sustainability and human health. However, the detection of nanoplastics (NPLs) remains challenging due to limitations in methodology and instrumentation. Herein, a “green approach” to surface-enhanced Raman spectroscopy (SERS) was exploited to detect polystyrene nanospheres (PSNSs) in water, employing an untreated filter paper and a simple syringe-filtration set-up. This SERS protocol not only enabled the filtration of nano-sized PSNSs which are smaller than the pore size of the ordinary filter paper but also offered SERS enhancement by utilizing quasi-spherical-shaped silver nanoparticles (AgNPs) as the SERS-active substrate. The filtering of NPLs was accomplished by adding an aggregating agent to the nanoparticles mixture, which caused the aggregation of NPLs and AgNPs, resulting in a larger cluster and more hot spots for SERS detection. The optimal aggregating agent and its concentration, as well as the volume ratio between AgNPs and NPLs, were also optimized. This SERS method successfully detected and quantified PSNSs of various sizes (i.e., 100, 300, 460, 600, and 800 nm) down to a limit of detection (LOD) of about 0.31 μg/mL. The method was also validated against the presence of several interferents (i.e., salts, sugars, amino acids, and surfactants) and was proven practical, as evidenced by the detection of 800-nm PSNSs in drinking and tap water (LODs of 1.47 and 1.55 μg/mL, respectively).","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141489478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A photoelectrochemical (PEC) biosensor with a wide detection linear range was developed for neuron-specific enolase (NSE) sensitive detection, which realized by a photocurrent polarity transition strategy mediated by quercetin. The coupling reaction between Cr(Ⅵ) and quercetin drive the signal polarity from anodic to cathodic. When quercetin in the test solution only, the photogenerated electrons transferred to the electrode to generate anodic photocurrent. When the target was detected, the signal probe was treated and released Cr(Ⅵ), which interact with quercetin and the electrons transfer direction was changed to achieve signal polarity conversion. Meanwhile, protoporphyrin-sensitized Bi: SrTiO3 nanocubes were used as the matrix photoactive materials to provide basic photocurrent. The doping of Bi element would prefer the bandgap of SrTiO3, and the organic-inorganic composite material has good photostability and chemical stability, that can maintain stable photoelectric properties over a long period of time. Such a novelty signal polarity transition strategy greatly broadened the sensor detection range of 0.00007 ~170 ng/mL and obtained a relative low detection limit (25 fg/mL), which greatly improved the detection sensitivity and accuracy of the biosensor
{"title":"Photoelectrochemical signal polarity transition mediated by quercetin for the detection of neuron specific enolase","authors":"Rui Xu, Chenyu Jiang, Qin Wei","doi":"10.1039/d4an00764f","DOIUrl":"https://doi.org/10.1039/d4an00764f","url":null,"abstract":"A photoelectrochemical (PEC) biosensor with a wide detection linear range was developed for neuron-specific enolase (NSE) sensitive detection, which realized by a photocurrent polarity transition strategy mediated by quercetin. The coupling reaction between Cr(Ⅵ) and quercetin drive the signal polarity from anodic to cathodic. When quercetin in the test solution only, the photogenerated electrons transferred to the electrode to generate anodic photocurrent. When the target was detected, the signal probe was treated and released Cr(Ⅵ), which interact with quercetin and the electrons transfer direction was changed to achieve signal polarity conversion. Meanwhile, protoporphyrin-sensitized Bi: SrTiO3 nanocubes were used as the matrix photoactive materials to provide basic photocurrent. The doping of Bi element would prefer the bandgap of SrTiO3, and the organic-inorganic composite material has good photostability and chemical stability, that can maintain stable photoelectric properties over a long period of time. Such a novelty signal polarity transition strategy greatly broadened the sensor detection range of 0.00007 ~170 ng/mL and obtained a relative low detection limit (25 fg/mL), which greatly improved the detection sensitivity and accuracy of the biosensor","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141462635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The development of ultrasensitive and visual method is of great significance for molecular diagnosis at the point-of-care. In this study, we have integrated recombinase polymerase amplification (RPA) with the CRISPR-Cas12a system to design an ultrasensitive strategy for visual nucleic acid testing. RPA is utilized to amplify the target nucleic acid, producing amplicons that activate the single-stranded DNase property of CRISPR-Cas12a. The activated CRISPR-Cas12a then degrades the single-stranded DNA on magnetic nanoparticles (MNPs), releasing immobilized GOx from MNPs for catalyzing the chromogenic substrate. The developed method exhibits remarkable sensitivity, successfully detecting as low as 10 aM (~6 copies/μL) of the target nucleic acid by visual colour changes in solution. The instrumental limit of detection is calculated to be 2.86 aM (~2 copies/μL), comparable to the sensitivity of polymerase chain reaction (PCR). Importantly, this approach only requires isothermal incubation operation and does not involve costly instruments. The method has been validated by visually detecting the SARS-CoV-2 RNA gene fragment within 50 minutes. With its ultrasensitivity, simplicity of operation, and potential for integration into a point-of-care detection kit, this strategy holds great promise for nucleic acid testing in various settings.
{"title":"CRISPR-Cas12a-based ultrasensitive assay for visual detection of SARS-CoV-2 RNA","authors":"Shaohua Gong, Kexin Song, Wei Pan, Na Li, Bo Tang","doi":"10.1039/d4an00479e","DOIUrl":"https://doi.org/10.1039/d4an00479e","url":null,"abstract":"The development of ultrasensitive and visual method is of great significance for molecular diagnosis at the point-of-care. In this study, we have integrated recombinase polymerase amplification (RPA) with the CRISPR-Cas12a system to design an ultrasensitive strategy for visual nucleic acid testing. RPA is utilized to amplify the target nucleic acid, producing amplicons that activate the single-stranded DNase property of CRISPR-Cas12a. The activated CRISPR-Cas12a then degrades the single-stranded DNA on magnetic nanoparticles (MNPs), releasing immobilized GOx from MNPs for catalyzing the chromogenic substrate. The developed method exhibits remarkable sensitivity, successfully detecting as low as 10 aM (~6 copies/μL) of the target nucleic acid by visual colour changes in solution. The instrumental limit of detection is calculated to be 2.86 aM (~2 copies/μL), comparable to the sensitivity of polymerase chain reaction (PCR). Importantly, this approach only requires isothermal incubation operation and does not involve costly instruments. The method has been validated by visually detecting the SARS-CoV-2 RNA gene fragment within 50 minutes. With its ultrasensitivity, simplicity of operation, and potential for integration into a point-of-care detection kit, this strategy holds great promise for nucleic acid testing in various settings.","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141461735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mass spectrometry imaging (MSI) is used for visualizing the distribution of components in solid samples, such as biological tissues, and requires a technique to ionize the components from local areas of the sample. Tapping-mode scanning probe electrospray ionization (t-SPESI) uses an oscillating capillary probe to extract components from a local area of a sample with a small volume of solvent and to perform electrospray ionization of those components at high speed. MSI can be conducted by scanning the sample surface with a capillary probe. To ensure stable extraction and ionization for MSI, the probe oscillation during measurements must be understood. In this study, we examined the changes in oscillation amplitude and phase due to the interaction between the oscillating probe and the brain tissue section when the probe tip was dynamically brought close to the sample surface. The changes in the probe oscillation depended on the oscillation frequency and polarity of the bias voltage applied to the solvent because an electrostatic force shifted the frequency of the probe oscillation. These findings suggest that controlling the probe oscillation frequency is important for stabilizing MSI by t-SPESI.
{"title":"Probe Oscillation Control in Tapping-mode Scanning Probe Electrospray Ionization for Stabilization of Mass Spectrometry Imaging","authors":"Mengze Sun, Yoichi Otsuka, Maki Okada, Shuichi Shimma, Michisato Toyoda","doi":"10.1039/d4an00712c","DOIUrl":"https://doi.org/10.1039/d4an00712c","url":null,"abstract":"Mass spectrometry imaging (MSI) is used for visualizing the distribution of components in solid samples, such as biological tissues, and requires a technique to ionize the components from local areas of the sample. Tapping-mode scanning probe electrospray ionization (t-SPESI) uses an oscillating capillary probe to extract components from a local area of a sample with a small volume of solvent and to perform electrospray ionization of those components at high speed. MSI can be conducted by scanning the sample surface with a capillary probe. To ensure stable extraction and ionization for MSI, the probe oscillation during measurements must be understood. In this study, we examined the changes in oscillation amplitude and phase due to the interaction between the oscillating probe and the brain tissue section when the probe tip was dynamically brought close to the sample surface. The changes in the probe oscillation depended on the oscillation frequency and polarity of the bias voltage applied to the solvent because an electrostatic force shifted the frequency of the probe oscillation. These findings suggest that controlling the probe oscillation frequency is important for stabilizing MSI by t-SPESI.","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141461578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Precise quantitative analysis of surface-enhanced Raman spectroscopy (SERS) in uncontrollable environment still faces a significant obstacle due to the poor reproducibility of Raman signals. Herein, we propose a facile method to fabricate self-calibration substrate based on flexible Polyvinyl Alcohol (PVA) film comprising assemblies of Prussian blue (PB) and Au NPs (PB@Au) for reliable detection. The PB cores were coated with Au shell through a simple electrostatic interaction, forming the core-shell nanostructure PB@Au assemblies within the PVA. The Au outer layer provided identical trends in enhancement for both PB core and neighboring targets, while PB cores served as internal standard (IS) to correct the signal fluctuations. The prevention of competitive adsorption on the metal surface between targets and ISs was achieved. The proposed PVA/PB@Au film exhibited enhanced stability of Raman signals after IS correction, resulting in improved spot-to-spot and batch-to-batch reproducibility with significantly reduced standard deviation (RSD) values from 11.42% and 25.02% to 4.43% and 9.39%, respectively. Simultaneously, higher accuracy in quantitative analysis of 4-mercaptobenzoic acid (4-MBA) and Malachite green (MG) were achieved with the fitting coeffcient (R2) values improving from 0.9675 and 0.9418 to 0.9974 and 0.9832, respectively. Moreover, the PVA/PB@Au film was successfully applied to detect the residual MG from real-life fish. This work provides an avenue to improve the reproducibility of Raman signals for flexible SERS substrates in detection of residue under varied and complex conditions.
{"title":"A Self-Calibrating Flexible SERS Substrate Incorporated PB@Au Assemblies for Reliable and Reproducible Detection","authors":"Jie Zhou, Huiting Wang, Yaxian Chen, Dongxue Lin, Ling Zhang, Zhi-Qiang Xing, Qian Zhang, Jiarui Xia","doi":"10.1039/d4an00151f","DOIUrl":"https://doi.org/10.1039/d4an00151f","url":null,"abstract":"Precise quantitative analysis of surface-enhanced Raman spectroscopy (SERS) in uncontrollable environment still faces a significant obstacle due to the poor reproducibility of Raman signals. Herein, we propose a facile method to fabricate self-calibration substrate based on flexible Polyvinyl Alcohol (PVA) film comprising assemblies of Prussian blue (PB) and Au NPs (PB@Au) for reliable detection. The PB cores were coated with Au shell through a simple electrostatic interaction, forming the core-shell nanostructure PB@Au assemblies within the PVA. The Au outer layer provided identical trends in enhancement for both PB core and neighboring targets, while PB cores served as internal standard (IS) to correct the signal fluctuations. The prevention of competitive adsorption on the metal surface between targets and ISs was achieved. The proposed PVA/PB@Au film exhibited enhanced stability of Raman signals after IS correction, resulting in improved spot-to-spot and batch-to-batch reproducibility with significantly reduced standard deviation (RSD) values from 11.42% and 25.02% to 4.43% and 9.39%, respectively. Simultaneously, higher accuracy in quantitative analysis of 4-mercaptobenzoic acid (4-MBA) and Malachite green (MG) were achieved with the fitting coeffcient (R<small><sup>2</sup></small>) values improving from 0.9675 and 0.9418 to 0.9974 and 0.9832, respectively. Moreover, the PVA/PB@Au film was successfully applied to detect the residual MG from real-life fish. This work provides an avenue to improve the reproducibility of Raman signals for flexible SERS substrates in detection of residue under varied and complex conditions.","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141461660","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yao Xiao, Taomei Peng, Yuxiao Luo, Lei Jiao, Taixing Huang, He Li
Manganese dioxide (MnO2) nanosheets possess unique physical and chemical properties, making them widely applicable in various fields such as chemicals and biomedicine. Although MnO2 nanosheets have been produced by bottom-up wet chemistry synthesis methods, their scale is below the gram level an requires a long processing time, restricting their effective application from laboratory to market. We report a facile, green method and scalable synthesis of MnO2 nanosheets by mixing Shiranui mandarin orange juice and KMnO4 for 30 minutes. We produced more than a grams (1.095) of MnO2 nanosheets with 0.65 nm mean thickness, 50 nm mean lateral size. Furthermore, we established a visual colorimetric biosensing strategy based on MnO2 nanosheets for assay of glutathione (GSH) and Cardiac troponin I (cTnI), emerging high sensitivity and feasibility in clinical sample. GSH with a limit of detection of 0.08 nM and cTnI with a limit of detection of 0.70 pg mL-1. Meanwhile, it can be real-time monitored by smartphone-enabled biosensing strategy, which can provide a realize point-of-care testing in remote areas.
{"title":"Facile, Green and Scalable Synthesis of Single-Layer Manganese Dioxide Nanosheets and its Applications for GSH and cTnl Colorimetric Detection","authors":"Yao Xiao, Taomei Peng, Yuxiao Luo, Lei Jiao, Taixing Huang, He Li","doi":"10.1039/d4an00689e","DOIUrl":"https://doi.org/10.1039/d4an00689e","url":null,"abstract":"Manganese dioxide (MnO2) nanosheets possess unique physical and chemical properties, making them widely applicable in various fields such as chemicals and biomedicine. Although MnO2 nanosheets have been produced by bottom-up wet chemistry synthesis methods, their scale is below the gram level an requires a long processing time, restricting their effective application from laboratory to market. We report a facile, green method and scalable synthesis of MnO2 nanosheets by mixing Shiranui mandarin orange juice and KMnO4 for 30 minutes. We produced more than a grams (1.095) of MnO2 nanosheets with 0.65 nm mean thickness, 50 nm mean lateral size. Furthermore, we established a visual colorimetric biosensing strategy based on MnO2 nanosheets for assay of glutathione (GSH) and Cardiac troponin I (cTnI), emerging high sensitivity and feasibility in clinical sample. GSH with a limit of detection of 0.08 nM and cTnI with a limit of detection of 0.70 pg mL-1. Meanwhile, it can be real-time monitored by smartphone-enabled biosensing strategy, which can provide a realize point-of-care testing in remote areas.","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141462447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Compositional analysis (CA)—identification and quantification of the system constituents—is the most fundamental and decisive approach to investigate the system of interest. Pyrolysis mass spectrometry (MS) with high resolution over 10,000 is very effective for chemical identification and directly applicable to polymer materials regardless of their solubilities; however, it is less helpful for quantification especially when the references, i.e., pure constituents, are unknown, non-isolable and thus unpreparable. To compensate this weakness, herein we propose reference-free quantitative mass spectrometry (RQMS) with enhanced quantification accuracy assisted by synchronized thermogravimetry (TG). The key to success lies in correlating the instantaneous weight loss from TG with MS signal, enabling the quantitative evaluation of the distinct ionization efficiency for each fragment individually. The determined ionization efficiencies allow conversion of MS signal intensities of pyrolyzed fragments into weight abundances. In a benchmark test using ternary polymer systems, this new framework named TG-RQMS demonstrates accurate CA within ±1.3 wt% errors without using any knowledge nor spectra of the references. This simple yet accurate and versatile CA method would be an invaluable tool to investigate polymer materials whose composition is hardly accessible via other analytical methods.
成分分析（CA）--系统成分的鉴定和定量--是研究相关系统的最基本、最具决定性的方法。热解质谱（MS）的分辨率高达 10,000 分以上，对化学鉴定非常有效，可直接用于聚合物材料（无论其溶解度如何）；但它对定量的帮助较小，尤其是当参照物（即纯成分）未知、不可分离，因而无法定量时。为了弥补这一不足，我们在此提出了无参照物定量质谱法（RQMS），在同步热重仪（TG）的辅助下提高了定量精度。成功的关键在于将热重仪测得的瞬时重量损失与质谱信号相关联，从而对每个片段的不同电离效率进行定量评估。根据确定的电离效率，可将热解片段的 MS 信号强度转换为重量丰度。在使用三元聚合物体系进行的基准测试中，这种名为 TG-RQMS 的新框架在不使用任何知识或参照物光谱的情况下证明了 CA 的准确性，误差在 ±1.3 wt% 以内。这种简单而准确的多功能 CA 方法将成为研究聚合物材料的宝贵工具，因为其他分析方法很难获得这些材料的成分。
{"title":"Thermogravimetry-Synchronized, Reference-Free Quantitative Mass Spectrometry for Accurate Compositional Analysis of Polymer Systems Without Prior Knowledge of Constituents","authors":"Yusuke Hibi, Shiho Uesaka, Masanobu Naito","doi":"10.1039/d4an00624k","DOIUrl":"https://doi.org/10.1039/d4an00624k","url":null,"abstract":"Compositional analysis (CA)—identification and quantification of the system constituents—is the most fundamental and decisive approach to investigate the system of interest. Pyrolysis mass spectrometry (MS) with high resolution over 10,000 is very effective for chemical identification and directly applicable to polymer materials regardless of their solubilities; however, it is less helpful for quantification especially when the references, i.e., pure constituents, are unknown, non-isolable and thus unpreparable. To compensate this weakness, herein we propose reference-free quantitative mass spectrometry (RQMS) with enhanced quantification accuracy assisted by synchronized thermogravimetry (TG). The key to success lies in correlating the instantaneous weight loss from TG with MS signal, enabling the quantitative evaluation of the distinct ionization efficiency for each fragment individually. The determined ionization efficiencies allow conversion of MS signal intensities of pyrolyzed fragments into weight abundances. In a benchmark test using ternary polymer systems, this new framework named TG-RQMS demonstrates accurate CA within ±1.3 wt% errors without using any knowledge nor spectra of the references. This simple yet accurate and versatile CA method would be an invaluable tool to investigate polymer materials whose composition is hardly accessible via other analytical methods.","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141453014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Machine learning (ML) is increasingly applied across various fields, including chemistry, for molecular design and optimizing reaction parameters. Yet, applying ML to experimental data is challenging due to the limited number of synthesized samples, which restricts its broader application in device development. In energy-harvesting, photoanodes are crucial for solar-driven water splitting, generating hydrogen and oxygen. We explored electrodes like hematite and bismuth vanadate for photocatalytic uses, noting varied photoelectrochemical performances despite similar preparations. To understand this variability, we applied a data-driven ML approach, predicting photocurrent values and identifying key performance influencers even with limited experimental data in the research development of inorganic device. Traditional ML methods used multiple algorithms, obscuring the influence of specific factors. We introduced a novel methodology, incorporating clustering to manage multicollinearity from correlated analytical data and Shapley analysis for clear interpretation of contributions to performance prediction. This method was validated on hematite and bismuth vanadate, showing superior predictability and factor identification, then extended to tungsten oxide and bismuth vanadate heterojunction photoanodes. Despite their complexity, our approach achieved determination coefficients (R2) with a prediction accuracy over 0.85, successfully pinpointing performance-determining factors, demonstrating the robustness of the new scheme in advancing photodevice research.
机器学习（ML）越来越多地应用于包括化学在内的各个领域，用于分子设计和优化反应参数。然而，由于合成样品的数量有限，将 ML 应用于实验数据具有挑战性，这限制了其在设备开发中的广泛应用。在能量收集领域，光阳极对于太阳能驱动的水分裂、产生氢气和氧气至关重要。我们探索了赤铁矿和钒酸铋等电极的光催化用途，发现尽管制备方法相似，但光电化学性能却各不相同。为了理解这种差异，我们在无机器件的研究开发中采用了数据驱动的 ML 方法，即使实验数据有限，也能预测光电流值并确定关键的性能影响因素。传统的 ML 方法使用多种算法，掩盖了特定因素的影响。我们引入了一种新方法，通过聚类来管理相关分析数据的多重共线性，并通过 Shapley 分析来明确解释对性能预测的贡献。这种方法在赤铁矿和钒酸铋上进行了验证，显示出卓越的可预测性和因素识别能力，然后扩展到氧化钨和钒酸铋异质结光电阳极。尽管它们很复杂，但我们的方法达到了预测精度超过 0.85 的确定系数 (R2)，成功地找出了性能决定因素，证明了新方案在推进光电器件研究方面的稳健性。
{"title":"Robust methodology for PEC performance analysis of photoanodes using machine learning and analytical data","authors":"Moeko Tajima, Yuya Nagai, Siyan Chen, Zhenhua Pan, Kenji Katayama","doi":"10.1039/d4an00439f","DOIUrl":"https://doi.org/10.1039/d4an00439f","url":null,"abstract":"Machine learning (ML) is increasingly applied across various fields, including chemistry, for molecular design and optimizing reaction parameters. Yet, applying ML to experimental data is challenging due to the limited number of synthesized samples, which restricts its broader application in device development. In energy-harvesting, photoanodes are crucial for solar-driven water splitting, generating hydrogen and oxygen. We explored electrodes like hematite and bismuth vanadate for photocatalytic uses, noting varied photoelectrochemical performances despite similar preparations. To understand this variability, we applied a data-driven ML approach, predicting photocurrent values and identifying key performance influencers even with limited experimental data in the research development of inorganic device. Traditional ML methods used multiple algorithms, obscuring the influence of specific factors. We introduced a novel methodology, incorporating clustering to manage multicollinearity from correlated analytical data and Shapley analysis for clear interpretation of contributions to performance prediction. This method was validated on hematite and bismuth vanadate, showing superior predictability and factor identification, then extended to tungsten oxide and bismuth vanadate heterojunction photoanodes. Despite their complexity, our approach achieved determination coefficients (R2) with a prediction accuracy over 0.85, successfully pinpointing performance-determining factors, demonstrating the robustness of the new scheme in advancing photodevice research.","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141452916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Asim Syed Sheeraz, Edoth Aiswarya, B. N. Kumara, Joseph Sonia, Relisha Viyona Rodrigues, Nazmin Sheikh, Sachin Vidhyasagar, RACHANA A KUNDER, Selvakumar Elangovan, Priti Sundar Mohanty, K. Sudhakara Prasad
Nowadays, kidney dysfunction is becoming a common health issue due to the modernized lifestyle. Even though medications are commercially available to treat kidney diseases, early diagnosis is vital and challenging. Clinically, measuring urine creatinine and pH has gained significant interest as a way to diagnose kidney diseases early. In the present work, we have attempted to develop a low-cost, robust, accurate and naked-eye colorimetric method to determine both creatinine levels and pH variations in an artificial urine samples using simple 3D-printed hybrid microfluidic device. Creatinine presence was identified by incorporation of traditional Jaffe test onto the hybrid paper–PMMA microfluidic device and pH (4-8) have been identified by utilizing simple anthocyanin test. Notably, the tests were established without employing any sophisticated or costly instrument clusters. The developed 3D-printed microfluidic probe showed a limit of detection (LOD) of 0.04 mM for creatinine over a concentration range of 1-10 mM, with a regression coefficient (R2) of 0.995 in the laboratory conditions. Interestingly the experimental data with artificial urine exhibited a wide linear range from 0.1 mM to 5 mM under different pH value ranging from 4 to 8 in the presence of matrices other than proteins commonly found in patient urine samples, which point towards the potential use for present method for pre-clinical analysis. Since the wide linear range under artificial urine samples falls well below the clinically relevant concentrations of urine creatine in humans (0.07-0.27 mM), the developed lab-on-chip device is further suitable for clinical evaluation with proper ethical clearance. The 3D-printed hybrid microfluidic colorimetry based creatinine detection and pH indicator platform could be beneficial in the healthcare sector due to the on-spot testing capabilities, cost-effectiveness, ease of use, robustness, and instrument-free approach.
{"title":"Additive Manufactured Paper-PMMA Hybrid Microfluidic Chip for Simultaneous Monitoring of artificial urine Creatinine and pH.","authors":"Asim Syed Sheeraz, Edoth Aiswarya, B. N. Kumara, Joseph Sonia, Relisha Viyona Rodrigues, Nazmin Sheikh, Sachin Vidhyasagar, RACHANA A KUNDER, Selvakumar Elangovan, Priti Sundar Mohanty, K. Sudhakara Prasad","doi":"10.1039/d4an00796d","DOIUrl":"https://doi.org/10.1039/d4an00796d","url":null,"abstract":"Nowadays, kidney dysfunction is becoming a common health issue due to the modernized lifestyle. Even though medications are commercially available to treat kidney diseases, early diagnosis is vital and challenging. Clinically, measuring urine creatinine and pH has gained significant interest as a way to diagnose kidney diseases early. In the present work, we have attempted to develop a low-cost, robust, accurate and naked-eye colorimetric method to determine both creatinine levels and pH variations in an artificial urine samples using simple 3D-printed hybrid microfluidic device. Creatinine presence was identified by incorporation of traditional Jaffe test onto the hybrid paper–PMMA microfluidic device and pH (4-8) have been identified by utilizing simple anthocyanin test. Notably, the tests were established without employing any sophisticated or costly instrument clusters. The developed 3D-printed microfluidic probe showed a limit of detection (LOD) of 0.04 mM for creatinine over a concentration range of 1-10 mM, with a regression coefficient (R2) of 0.995 in the laboratory conditions. Interestingly the experimental data with artificial urine exhibited a wide linear range from 0.1 mM to 5 mM under different pH value ranging from 4 to 8 in the presence of matrices other than proteins commonly found in patient urine samples, which point towards the potential use for present method for pre-clinical analysis. Since the wide linear range under artificial urine samples falls well below the clinically relevant concentrations of urine creatine in humans (0.07-0.27 mM), the developed lab-on-chip device is further suitable for clinical evaluation with proper ethical clearance. The 3D-printed hybrid microfluidic colorimetry based creatinine detection and pH indicator platform could be beneficial in the healthcare sector due to the on-spot testing capabilities, cost-effectiveness, ease of use, robustness, and instrument-free approach.","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":4.2,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141452912","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antibodies are crucial in various biological applications due to their specific binding to target molecules, altering protein function and structure. The advent of single-chain antibodies such as nanobodies has paved the way for broader applicability in both research and therapies due to their small size and efficient tissue penetration. Recently, several approaches have been reported to optically control the antigen-binding affinity of nanobodies. Here, we show an alternative strategy for creating photo-activatable nanobodies. By fusing the photocleavable protein PhoCl with the N-terminus of the nanobody (named optoNb60), we successfully demonstrated light-dependent restoration of the antigen-binding ability and the following modulation of the activity of a target protein, the beta-2 adrenergic receptor. Moreover, the activation of optoNb60 was monitored by the fluorescence changes upon photoconversion. The compatibility of the uncaging design with the previously reported optogenetic molecules using nanobodies will contribute to the further optimization of the response capabilities of existing optogenetic tools, thereby expanding their applicability.
抗体能与目标分子特异性结合，改变蛋白质的功能和结构，因此在各种生物应用中至关重要。单链抗体（如纳米抗体）因其体积小、组织穿透力强，为更广泛地应用于研究和治疗铺平了道路。最近，有几种方法被报道用于光学控制纳米抗体的抗原结合亲和力。在这里，我们展示了另一种制造光活化纳米抗体的策略。通过将可光裂解蛋白 PhoCl 与纳米抗体（命名为 optoNb60）的 N 端融合，我们成功地证明了光依赖性抗原结合能力的恢复，以及随后对靶蛋白--β-2 肾上腺素能受体--活性的调节。此外，我们还通过光电转换时的荧光变化监测了 optoNb60 的活化情况。开笼设计与之前报道的使用纳米抗体的光遗传分子的兼容性将有助于进一步优化现有光遗传工具的反应能力，从而扩大其适用范围。
{"title":"Optical control of nanobody-mediated protein activity modulation with a photocleavable fluorescent protein.","authors":"Mizuki Endo, Saki Tomizawa, Qiaoyue Kuang, Takeaki Ozawa","doi":"10.1039/d4an00433g","DOIUrl":"https://doi.org/10.1039/d4an00433g","url":null,"abstract":"<p><p>Antibodies are crucial in various biological applications due to their specific binding to target molecules, altering protein function and structure. The advent of single-chain antibodies such as nanobodies has paved the way for broader applicability in both research and therapies due to their small size and efficient tissue penetration. Recently, several approaches have been reported to optically control the antigen-binding affinity of nanobodies. Here, we show an alternative strategy for creating photo-activatable nanobodies. By fusing the photocleavable protein PhoCl with the N-terminus of the nanobody (named optoNb60), we successfully demonstrated light-dependent restoration of the antigen-binding ability and the following modulation of the activity of a target protein, the beta-2 adrenergic receptor. Moreover, the activation of optoNb60 was monitored by the fluorescence changes upon photoconversion. The compatibility of the uncaging design with the previously reported optogenetic molecules using nanobodies will contribute to the further optimization of the response capabilities of existing optogenetic tools, thereby expanding their applicability.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":null,"pages":null},"PeriodicalIF":3.6,"publicationDate":"2024-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141445592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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